A large number of the research activities associated with the MAC require the use of molecular biology techniques that employ synthetic oligonucleotide primers or that require substantial levels of DNA sequencing. The concept of centralized research core facilities has gained wide acceptance as an efficient strategy for operating expensive and complex instrumentation in support of a large number of diverse research programs. To meet the needs of the MAC research programs, we propose here to establish a Molecular biology Core facility with the following specific aims: (1) to provide efficient and accurate automated DNA sequencing services to MAC research programs. (2) to provide high quality synthetic oligonucleotides to MAC investigators. The core will provide consultation with regard to optimization of experimental techniques (e.g., optimization of DNA primer design), standardization and quality control of DNA synthesis and sequencing reaction conditions, and assistance with the interpretation of experimental data. It is anticipated that these core services will substantially expedite the MAC research programs, maximize productivity, and minimize expenses relative to DNA sequencing and synthesis.